This invention is concerned with an adapter to enable a dry cell battery to be used in an application in which it might be charging or discharging for which it is electrically acceptable but for which it is physically too small.
Batteries in flash lights, portable radios or so called chargers and other equipment are usually supported in a tube or clips or other mechanical contrivances so that they are securely held in electrical contact with the terminals of the circuit or element which they are to supply or from which they are to be supplied (charged). The support means may hold a single battery between the terminals or a plurality of batteries in end to end relationship may be so held but almost always the support means are arranged to receive a battery of particular transverse cross sectional dimensions.
As is well known, there are generally available several differently dimensioned batteries which have similar electrical discharge and charging characteristics. It frequently occurs than when a physically large battery is needed there is available only a battery of a smaller size but one which is electrically acceptable.
Further, as batteries are reduced in size with advancing technology, it becomes technically and economically desirable to use the new and smaller batteries in equipment designed specifically to receive older and larger batteries. For example, a nickel/cadmium AA battery has similar electrical discharge characteristics to a zinc/carbon D battery but of course as it is rechargeable it is desirable to be able to use such a battery in place of the larger zinc/carbon battery.
Major differences between existing large and small batteries is their working lives. Many pieces of equipment such as, for example, flash lights are designed to receive large batteries that fit them for long and continuous use but in practice those pieces of equipment may be used for only short periods with long intervals of non-use between those periods. During those periods of non-use the battery deteriorates or, because of faulty terminals in the equipment, discharges. In many cases these long periods of non-use can be foreseen but because of the physical design characteristics of the pieces of equipment one is obliged to use a large and expensive battery knowing that were its use physically possible a small, cheaper battery having a shorter working life would be quite adequate.